/*
 * Copyright 2010 Facebook, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.harusoft.interlock;

import java.util.LinkedList;

public class SessionEvents {

	private static LinkedList<AuthListener> mAuthListeners = 
			new LinkedList<AuthListener>();
	private static LinkedList<LogoutListener> mLogoutListeners = 
			new LinkedList<LogoutListener>();

	/**
	 * Associate the given listener with this Facebook object. The listener's
	 * callback interface will be invoked when authentication events occur.
	 * 
	 * @param listener
	 *            The callback object for notifying the application when auth
	 *            events happen.
	 */
	public static void addAuthListener(AuthListener listener) {
		mAuthListeners.add(listener);
	}

	/**
	 * Remove the given listener from the list of those that will be notified
	 * when authentication events occur.
	 * 
	 * @param listener
	 *            The callback object for notifying the application when auth
	 *            events happen.
	 */
	public static void removeAuthListener(AuthListener listener) {
		mAuthListeners.remove(listener);
	}

	/**
	 * Associate the given listener with this Facebook object. The listener's
	 * callback interface will be invoked when logout occurs.
	 * 
	 * @param listener
	 *            The callback object for notifying the application when log out
	 *            starts and finishes.
	 */
	public static void addLogoutListener(LogoutListener listener) {
		mLogoutListeners.add(listener);
	}

	/**
	 * Remove the given listener from the list of those that will be notified
	 * when logout occurs.
	 * 
	 * @param listener
	 *            The callback object for notifying the application when log out
	 *            starts and finishes.
	 */
	public static void removeLogoutListener(LogoutListener listener) {
		mLogoutListeners.remove(listener);
	}

	public static void onLoginSuccess() {
		for (AuthListener listener : mAuthListeners) {
			listener.onAuthSucceed();
		}
	}

	public static void onLoginError(String error) {
		for (AuthListener listener : mAuthListeners) {
			listener.onAuthFail(error);
		}
	}

	public static void onLogoutBegin() {
		for (LogoutListener l : mLogoutListeners) {
			l.onLogoutBegin();
		}
	}

	public static void onLogoutFinish() {
		for (LogoutListener l : mLogoutListeners) {
			l.onLogoutFinish();
		}   
	}

	/**
	 * Callback interface for authorization events.
	 *
	 */
	 public static interface AuthListener {

		 /**
		  * Called when a auth flow completes successfully and a valid OAuth 
		  * Token was received.
		  * 
		  * Executed by the thread that initiated the authentication.
		  * 
		  * API requests can now be made.
		  */
		 public void onAuthSucceed();

		 /**
		  * Called when a login completes unsuccessfully with an error. 
		  *  
		  * Executed by the thread that initiated the authentication.
		  */
		 public void onAuthFail(String error);
	 }

	 /**
	  * Callback interface for logout events.
	  *
	  */ 
	 public static interface LogoutListener {
		 /**
		  * Called when logout begins, before session is invalidated.  
		  * Last chance to make an API call.  
		  * 
		  * Executed by the thread that initiated the logout.
		  */
		 public void onLogoutBegin();

		 /**
		  * Called when the session information has been cleared.
		  * UI should be updated to reflect logged-out state.
		  * 
		  * Executed by the thread that initiated the logout.
		  */
		 public void onLogoutFinish();
	 }

}
